摘要
目的研究甲醛和二甲苯联合染毒对小鼠神经系统的毒性作用及其机制,为综合评价室内装修材料中甲醛和二甲苯对人体健康的危害提供科学依据。方法选用健康清洁级昆明小鼠72只,按完全随机设计,将小鼠随机分为12组,每组6只,雌雄各半,分别为低剂量(5 mg/kg)、中剂量(10 mg/kg)、高剂量甲醛染毒组(20 mg/kg)和生理盐水对照组,低剂量(50 mg/kg)、中剂量(100 mg/kg)、高剂量二甲苯染毒组(150 mg/kg)和花生油对照组以及低剂量(2.5 mg/kg甲醛+25 mg/kg二甲苯)、中剂量(5 mg/kg甲醛+50 mg/kg二甲苯)、高剂量联合染毒组(10 mg/kg甲醛+75 mg/kg二甲苯)以及生理盐水+花生油(体积比1∶1)对照组;采用腹腔注射染毒,连续7 d。染毒结束后,采用Morris水迷宫实验和流式细胞凋亡对小鼠进行神经毒性的研究。结果与相应对照组相比,中、高剂量甲醛、二甲苯以及联合染毒组小鼠逃避潜伏期延长,差异均有统计学意义(P<0.05);与相同剂量联合染毒组比较,中、高剂量甲醛、二甲苯联合染毒组雌性小鼠逃避潜伏期缩短,差异均有统计学意义(P<0.05);随着染毒时间的延长,各染毒组小鼠总体逃避潜伏期呈缩短趋势。在空间探索实验中,与相应对照组相比,中、高剂量甲醛、二甲苯染毒组以及各剂量联合染毒组小鼠找到平台的时间延长,在原平台象限游泳时间缩短,原平台象限游泳距离占总距离百分比下降,差异均有统计学意义(P<0.05);与相同剂量联合染毒组比较,各剂量甲醛染毒组和中、高剂量二甲苯染毒组小鼠找到平台的时间缩短,高剂量甲醛染毒组和二甲苯染毒组雌性小鼠、雄性小鼠以及小鼠总体在原平台象限游泳时间延长,原平台象限游泳距离占总距离百分比上升,差异有统计学意义(P<0.05)。与相应对照组相比,各剂量甲醛、二甲苯以及联合染毒组小鼠海马细胞早期凋亡率以及高剂量甲醛、二甲苯以及联合染毒组晚期凋亡率均升高,差异均有统计学意义(P<0.05);且随着染毒剂量的升高,小鼠海马细胞早期、晚期凋亡率呈上升趋势。与相同剂量联合染毒组比较,中、高剂量甲醛、二甲苯染毒组小鼠早期凋亡率均下降,高剂量甲醛、二甲苯染毒组雌性小鼠、雄性小鼠和小鼠总体晚期凋亡率均下降,差异均有统计学意义(P<0.05)。结论甲醛和二甲苯联合染毒能降低小鼠的学习记忆能力,对神经系统具有一定毒性作用,且二者联合染毒具有一定的协同作用。
Objective To study the combined toxic effect of formaldehyde and xylene on neurobehavioral function of mice and the mechanism. Methods Seventy-two healthy clean Kunming mice were randomly divided into 12 groups：low dose of formaldehyde （5 mg/kg）,moderate dose （10 mg/kg）,high dose （20 mg/kg） as well as a negative control group with normal saline; low dose of xylene （50 mg/kg）,moderate dose （100 mg/kg）,high dose （150 mg/kg） as well as a negative control group with peanut oil; low dose of joint exposure （2.5 mg/kg formaldehyde＋25 mg/kg xylene）,moderate dose （5 mg/kg formaldehyde＋50 mg/kg xylene）, high dose （10 mg/kg formaldehyde＋75 mg/kg xylene） as well as a negative control group with normal saline ＋ peanut oil （1：1 ）; The treatments were conducted by peritoneal injection for seven consecutive days. After seven days of exposure ,the neurotoxicity was tested by Morris water maze and flow cytometry. Results In space training, compared with control group, the escape latency in all moderate and high dose groups significantly increased （P〈0.05）. And compared with the same dose groups of joint exposure, in female groups contaminated with moderate or high dose of formaldehyde or xylene, it decreased （P〈 0.05 ）with time-dependant manner. In space exploration experiment, compared with control group ,all groups except low dose groups of formaldehyde or xylene the time of finding the platform presented an ascend tendency （P〈0.05）, while the time and the percentage of swimming distance in target quadrant presented a descend tendency （P〈0.05）. While compared with the same dose groups of joint exposure, in all contaminated groups except low dose of xylene, the time of finding the platform decreased, in high dose groups of formaldehyde or xylene the time of swimming distance in target quadrant increased and the percentage of swimming distance in target quadrant presented an increase tendency （P〈0.05）. In all groups the early and advanced stage apoptosis rates of hippocampus cells increased dose-dependant manner（P〈0.05 ）. Compared with the same dose groups of joint exposure, in groups contaminated with moderate or high dose of formaldehyde or xylene, the early stage apoptosis rates decreased. In groups treated with high dose of formaldehyde or xylene, the advanced stage apoptosis rates decreased（P〈0.05）. Conclusion Joint exposure to formaldehyde and xylene may decrease the learning and memory abilities of mice and induce toxicity on nervous system. The joint neurotoxicity of formaldehyde and xylene is considered synergistic.
出处
《环境与健康杂志》
CAS
CSCD
北大核心
2012年第2期155-160,共6页
Journal of Environment and Health
基金
山西省自然科学基金(2009011049-2)
关键词
甲醛
二甲苯
联合染毒
水迷宫
海马细胞
Formaldehyde
Xylene
Joint exposure
Water maze
Hippocampal cells
